What Does "Clean Eating" Mean, Anyway?
Clean Eating / Food Quality
Food quality is typically used as a term referencing the micronutrient content of a food, i.e. favoring foods like fruits and vegetables over processed, refined foods like cereals and chips.
From a physiology perspective, we need certain quantities of micronutrients to avoid sickness, developing disease, and even regulating our endocrine system.
With this in mind, proponents of a "food quality" based approach will tell you that ever meal consumed should be the highest quality, most micronutrient dense, sources available. This would exclude the allowance of processed or refined foods - even if consumed within an individual's daily caloric (or macro) requirement. The paleo diet is the best example of this in recent history.
Pros of a Quality Based Approach
There are a lot of positives to a quality based approach that can even include overcoming autoimmune diseases.
When consuming a diet composed of nutrient dense foods, you are at a far lower risk for any vitamin and mineral deficiencies, resulting in less inflammation, increased immunity, and usually increased overall health as would be defined by clinical lab work.
Empirically, we have also see a lot of weight loss achieved on "clean eating" diets.
Cons of a Quality Based Approach
While it is undeniably "healthy" to only consume unrefined foods, minimally processed foods, and foods that would be considered acceptable within an ancestral approach, it is not always the easiest thing to do from a practical approach.
In most societies, food is part of social gatherings. By reducing the types of foods you are willing to eat, you are also reducing the likelihood of being able to actively participate in the eating portion of social gatherings. For most people, this isn't something you're willing to give up very easily.
There is no quantity control in quality based approaches. Paleo advocates will tell you to "eat when you're hungry, as long as it's paleo." Unfortunately, regardless of micronutrient content, CALORIES STILL MATTER. Chronic caloric underconsumption will yield long term metabolic adaptation, and chronic caloric overconsumption will yield body fat accumulation. This is an undeniable truth.
Finally, by limiting your food selections, you are also limiting the activity of specific enzymes within your body. Failing to consume a specific food or food group for long periods of time can reduce the enzymatic activity so much that you never fully regain the use of it. Lactase is a great example of this as long term dairy exclusion can create an inability to digest dairy later in life.
Stay tuned for the Quantity specific approach (flexible dieting) blog.